refactor: add string validation for feedback attrs and remove unused var (#1035)

rdagent/components/coder/CoSTEER/evaluators.py

@@ -70,6 +70,10 @@ class CoSTEERSingleFeedback(Feedback):
 
         if not isinstance(data["final_decision"], bool):
             raise ValueError(f"'final_decision' must be a boolean, not {type(data['final_decision'])}")
+
+        for attr in "execution", "return_checking", "code":
+            if data[attr] is not None and not isinstance(data[attr], str):
+                raise ValueError(f"'{attr}' must be a string, not {type(data[attr])}")
         return data
 
     def __str__(self) -> str:

rdagent/components/coder/data_science/pipeline/eval.py

@@ -62,7 +62,6 @@ class PipelineCoSTEEREvaluator(CoSTEEREvaluator):
             result = implementation.run(env=env, entry=f"python -m coverage run main.py --debug")
         else:
             result = implementation.run(env=env, entry=f"python -m coverage run main.py")
-        execute_ret_code = result.exit_code
         result.stdout = remove_eda_part(result.stdout)
         if result.exit_code != 0:
             stdout += f"Code failed to run. Please check the stdout:\n Following the stdout of the debug mode run:\n{result.stdout.strip()}\n"